FIG. 1 depicts a plan view of a portion of a conventional heat assisted magnetic recording (HAMR) transducer 10. The conventional HAMR transducer 10 includes a pole (not shown), coil(s) (not shown), and other components used in writing to a media (not shown). The conventional HAMR transducer 10 is coupled to a laser (not shown) for providing light energy to the HAMR transducer 10. In addition, the HAMR transducer includes a conventional waveguide 20 for directing light from the laser to a near field transducer (NFT) near the ABS.
The conventional waveguide 20 includes an entrance 22, a tapered region 24, and an exit 26 near the ABS. The tapered region 24 goes from a wider entrance 22 to a smaller cross-section. Thus, the exit 26 near the ABS is smaller in cross-section than the entrance 22. Note that the waveguide 20 in FIG. 1 is shown as tapering in the cross-track direction (left-right in FIG. 1). In some cases, the waveguide 20 may taper in the down track direction (out of the plane of the page in FIG. 1). The tapered region 24 confines the energy in the laser mode provided by the laser (not shown in FIG. 1) to a smaller waveguide mode.
FIG. 2 depicts the laser mode 30 and the conventional waveguide mode 28 for the conventional transducer 10. The entrance 22 for the waveguide 20 is also depicted in FIG. 2. Referring to FIGS. 1 and 2, the laser mode 30 corresponds to the laser spot at the entrance 22 of the waveguide 20. The waveguide mode 28 indicates the region for which energy is coupled into the waveguide 20. The entrance 22 is smaller than the mode 28 coupled into the waveguide 20. In the HAMR transducer 10 depicted in FIGS. 1-2, the laser energy/mode 30 is within the waveguide mode 28. Stated differently, the laser mode 30 is within the region 28 for which energy is coupled into the waveguide 12. Thus, the waveguide 20 provides energy to the ABS that may be used by the HAMR transducer 10 in writing to the media (not shown).
Although the conventional waveguide 20 functions, the location of the laser mode 30 may shift during fabrication of the HAMR transducer 10. For example, the laser may be aligned with the waveguide entrance 22 and then bonded. However, during the bonding process, the location of the laser may change. Thus, misalignments may occur between the laser mode 30 and the waveguide mode 28. As a result, the waveguide 20 may couple in less energy from the laser. Thus, performance of the conventional waveguide 20 may be adversely affected. In some cases, the misalignment is severe enough that the waveguide 20 does not couple in enough energy to meet the minimum standards of operation for the HAMR transducer 10. As a result, yield for fabrication of the conventional HAMR transducer 10 may be adversely affected.
Accordingly, what is needed is an improved method for fabricating a HAMR transducer.